Carbureter.



tical cross section of the carbureter.

UNITED STATES PATENT OFFICE.

BDLLIN ABELL, 0F BOSTON,` MASSACHUSETTS.

CARBURE'IER.

Application led November 9, 1911.

To all whom it may conce/rn Be it known that I, RoLmN ABELL, a citizen of the United States, and resident of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Carbureters, of which the following is a specification.

This invention relates to carbureters, and one of its objects is to insure prompt starting of the motor to which it is connected. This is accomplished by a construction which automatically closes all communication between the mixing chamber and the atmosphere when the carburetor is not in operation, providd the carburetor is supplied with fuel. The fuel feeding means and a primary air conduit coperate to form a seal of the Huid through which seal the first charge of air must be drawn by the suction of the motor. The first charge of air is compelled to pass through the sealed conduit and the sealing fluid is splashed upon the walls of the mixing chamber in a sufficient volume to insure a combustible charge which will be readily ignited regardless of the temperature of the air.

Another object of the invention is to provide thermostatic means for regulating the proportions of air and fuel, whether the carburetor is in operation or standing idle, so that the charges delivered tothe motor will be comparatlvely rich in fuel when the weather is cold, and comparatively lean when the weather is hot. It is well known to those skilled in the art that while a lean mixture is desirable in hot Weather, it will not be as readily ignited when the weather is cold.

Of the accompanying drawings which illustrate one form in which the invention may be embodied: Figure 1 represents a ver- Fig. 2 represents a horizontal section in the plane indicated by line 2-2 in Fig. 1.

The same reference characters indicate the same parts wherever they occur.

The carbureter constructed as illustrated comprises a casing 10 which provides a fuel A chamber 11, and a casin`12 which provides a mixing chamber 13. uel, such as gasolene or other hydrocarbon is delivered into the chamber 11 by a supply pipe 14 at the delivery end of which 1s a Vvalve 15. The valve is operated by a bell crank 16 to which is attached a float 17, whereby the quantity peciiication of Letters Patent.

Patented Oct. 26, 1915.

Serial No. 659,393.

of fuelin the chamber is maintained at a level indicated by line m.

The combustible charge which is mixed in the chamber 13 passes through an outlet 18 from which it is conducted to the motor by a suitable pipe or manifold (not shown). The wall of the mixing chamber 13 comprises a portion 19 which tapers downwardly and which is open at the bottom for the admission of air. The bottom of the casing 12 is provided with feet or lugs 20 which rest upon a plate or cover 21 of the casing 10 and which provide a suitable space between the two casings for the v, admission of air into the mixing chamber. A

The fuel in the chamber 11 passes through a duct 22 into a substantially vertical delivery nozzle or outlet 23. The fuel passes upwardly through the nozzle 23 and normally overflows the top of the nozzle, because the latter terminates below the level of the fuel indicated by line m. The duct 22 and delivery nozzle 23 are formed in a tube 24 which extends vertically through the chamber 11 and which is fastened to the bottom of the casing l0 by a nut 25. The nut holds the casing 10 against the plate or cover 21, thus practically closing the chamber 11 and at the same time affording means whereby the casing 10 may be quickly detached.

The well or chamber 26 within the tube 24 is closed at the bottom but open at the top for the admission of air. A sleeve 27 is disposed in the tube 24 and is free to slide vertically therein. This sleeve, as shown by Fig. 2, is in the form of an elongated pinion of which the crowns of the teeth engage the interior of the tube. The spaces between the teeth provide air passages through which air may pass downwardly, around the lower end of the sleeve and then upwardly through the annular space 2S between the interior of the sleeve and the exterior of the nozzle 23. This supply of air passes upwardly through the sleeve which extends into the mixing chamber 13, and is thus delivered into the mixing chamber. The upper end of the sleeve is screw-threaded loosely in a disk 30 whose diameter is slightly less than the internal diameter of the smaller end of the tapering portion 19. The disk 30 is, in effect, an air valve or piston, and by reason of its weight and that of the sleeve is adapted to normally close the inlet of the tapering portion 19. A post 31 is aiiixed to the plate 21 and extends loosely through the piston 30. A shoulder 32 near the lower end of the post is a stop for limiting the downward movement of the piston, While a nut 33 threaded upon the upper end of the post is a stop for limiting upward movement of the piston. The extreme upper position of the piston is represented by dotted lines. This post, in addition to limiting the up and down movement of the piston, has the funetion of preventing rotation of the piston, for a purpose hereinafter described.

A needle valve 34 is carried by the sleeve 27 and is adapted to control the discharge of fuel from the nozzle 23. The upper end of the needle valve is bored transversely for the reception of a horizontal pin 35 whereb Y the needle valve is suspended. The ends o the pin 35 enter the sleeve 27. As shown by Fig. 1, the hole in the needle valve through which the pin extends is slightly larger than the pin and is therefore adapted to permit the needle valve to move laterally and to assume whatever angle is required without causing the needle valve to bind in the nozzle The position of the several parts, as shown by Fig. 1, represents their normal positions when there is no vacuum in the mixing chamber. At this time the delivery nozzle 23 is nearly closed by the needle valve, but suflicient space is left between the nozzle and the valve for permitting the fuel to overflow into the well 26 so that the well may contain a supply offuel up to the level of the fuel in the supply chamber. Inasmuch as the lower end of thc sleeve 27 is below the level of the fuel in the well, the air passage through the sleeve is sealed and at the same time the air inlet to the mixing chamber is substantially closed. Now, therefore, when a vacuum is created in the mixing chamber by turnin the motor, an initial supply of air will be rawn from the sleeve and through the spaces between the teeth upon the interior thereof. The overflowed fuel in the bottom of the well will thus bc sucked into the mixing chamber and incidentally some of it will be deposited upon the interior of the tube to the maximum capacity of the tube for retaining such deposit. The first charge which passes from the carbureter will therefore be extremely rich in fuel and will be so readily combustible that the motor will begin to operate by its own power immediately. As the speed of the motor increases and produces an increased vacuum in the mixing chamber, the capacity of the sleeve 2T will be so taxed that the air piston or valve 30 will be lifted. As the piston is lifted it provides a gradually increasing air-opening directly into the mixin chamber and it is automatically adjuster? by the vacuum so that it will balance the vacuum in all positions. The supply of overflowed fuel in the bottom of the well 26 is soon volatilized and carried to the motor, and thereafter the fuel flowing from the delivery nozzle is entrained or volatilized by the upwardly rushing column of air which surrounds the needle valve. The needle valve, being supported by the sleeve 2T, moves up and down in unison with the piston 3U, thus varying the supply of fuel substantially in proportion to the supply of air. By means of this combination of valves the volume of the supply is automatically varied in accordance with the speed of the motor, while the proportion of the air and fuel remains substantially the same at all speeds except when the motor is first started, when, as previously explained, a relatively great proportion of fuel is supplied because of the quantity contained in the bottom of the well.

A device is provided which is adapted to vary the proportions of air and fuel as the temperature of the weather varies, to the end that more fuel will be supplied when the weather is cold than when it is hot. This device comprises a gear 36 in coperative relation with the teeth upon the exterior of the sleeve 27. The gear 36 is disposed in the space between the cover 21 and the casing 12 and is held in position by a stud 3T a portion of which is threaded in the cover 21. The teeth of the gear 36 and the teeth on the sleeve 27 are so formed as to offer no appreciable resistance to the up and down movement of the sleeve. A thermostatic coil 38 is attached to the gear 36 in such manner as to turn the gear in one direction when the surrounding temperature increases, and to turn the gear inthe opposite direction when the temperature decreases.

As shown by Fig. 2, the gear 36 has a series of holes 39 into one of which a tongue at the outer end of the thermostatie coil is inserted, while the inner end of the coil is anchored to the stud 37. A washer 40 is placed over the coil to keep it seated on the gear and keep the gear seated on the cover 21. This washer is preferably made of niaterial such as wood fiber, for example, which will not readily conduct heat. The casin 12 may be heated as hereinafter explainec The needle valve may be adjusted with relation to the coil 38 while the carburetor is fully assembled, by lifting the outer end of the coil out of the hole 39 which it occupies Iand by turning the gear until another hole is in position to receive the end of the coil.

One purpose of the post 31, previously described, is to prevent rotation of the valve 30. Now, therefore, when the sleeve 27 is rotated itfmoves up or down with relation to the valve 30 because of its threaded connection. In this Way the relation of the air and fuel valves is varied to vary the proportions of air and fuel. When the motor is running, the tension of the vacuum pulsates and thus keeps the sleeve 27 in a stateof constant agitation. This agitation fac1l1 tates the rotation of the gear 36 so that the coil may readily expand and contract and impart the desired rotary movement.

The casing l2 is formed with a Water jacket 4l surrounding the mixing chamber. When the carbureter is applied to a motor of the water-cooled type, thewater which is circulated through the jackets of the cylinders may be circulated also through the water jacket 3l of the carbureter while passing from the motor to the customary radiator.

The Words thermostat and thermostatic as u-sed throughout this specification and the appended claims do not contemplate a constant temperature, but are intended to indicate that the element 38 to which they relate is responsive to thermal variations.

I claim:

l. A carbureter comprising a mixing chamber for air and fuel, said chamber havmg an air inlet and an outlet for the charges, means for conducting fuel into said chamber, and thermostatic means outside said chamber' for decreasing the supply of fuel as the temperature rises, and for increasing the supply as the temperature falls.

2. A carbureter comprising a mixing chamber for air and fuel, said chamber having an air inlet and an outlet for the charges, a valve for controlling the admission of air through said inlet, means for conducting fuel to said chamber, a valve for controlling the supply of fuel, adjustable connections between said valves whereby opening and closing movement is transmitted from one to the other, and thermostatic means for regulating said connections to vary the relation of said valves.

3. A carbureter comprising a mixing chamber having an air inlet and an outlet for charges, a valve disposed in said inlet and adapted to be opened inwardly by a vacuum in said chamber and adapted to be closed by gravity, means for conducting fuel into said chamber, a valve for controlling the supply of fuel, means connecting the air valve and fuel valve for opening and closing the fuel valve when the air valve is opened and closed, said means being adjustable for varying the position of the fuel valve, and thcrmrtatic means upon the exterior of the carbureter for regulating said connectingmeans to vary the relation of said valves.

4. A carbureter comprising a casing having a mixing chamber, said chamber having an air inlet and an outlet a freely movable valve in said inlet adapted to open inwardly and to be closed by gravity, a fuel well open at the top, a fuel delivery nozzle arranged to discharge into said well, a sleeve loosely threaded through said air valveq and extending into said well beyond and outside the mouth of said fuel nozzle, the exterior of said sleeve having gear teeth, a valve carried by said sleeve for coperating with said fuel nozzle, a gear mounted to engage the teeth on said sleeve, and thermostatic means acting on said gear to turn it.

5. In a carbureter of the described class the combination of an air controlling valve VYand liquid controlling valve, and means for communicating motion from said air controlling valve to said liquidy controlling valve including the thermostat adapted to automatically regulate the movement of said liquid controllin valve, whereby the supply of combustib e fluid used may be varied to correspond with the variation of temperature.

6. In a device of the character set forth, the combination of a mixing duct, a jet nozzle, and means o erating to automatically vary the supply o liquid fuel to said nozzle in inverse roporton to the temperature of the air which enters the mixing duct.

7. In a device of the character set forth, the combination of a mixing duct, a jet nozzle, and a thermostatic valve arranged to vary the supply of liquid fuel to the jet nozzle inversely pro ortional to the temperature of the air W ich enters the mixing duct.

8. In a device of the character set forth, the combination of a mixing duct, a liquid fuel supply arranged to discharge into said duct, means for supplying air to said duct, and thermostatic means operative through engine temperature to automatically vary the proportions between the air and the liquid fuel supplied to said duct.

In testimony whereof I have affixed my signature, in presence of two witnesses.

ROLLIN ABELL. Witnesses:

DISCLAIMER.

1,158,359.-Rollz`n. Abell, Boston, Mass. CAnmzmon. Patent dated October 26, 1915. Disclaimer filed October 14, 1927, by the assgnees, Fannie Ska/fer and Margaret N. P. @album Hereby enter this disclaimer to that partJ of the claims in said specification which is in the following words, to wit:

8. In a device of the character set forth, the combination of a, mixing duct, a liquid fuel supply arranged to discharge into said duct, means for supplying air to said duct, and thermostatic means operative through engine tem erature to automatically vary the proportions between the air and the liquid fue supplied to said duct.

[Oficial Gazette November 1, 1.927.] 

